Notes from Effective C++ CD

During 1998, much of my time was devoted to designing and helping supervise the implementation of an electronic version of two of my books. The result was Effective C++ CD, an HTML implementation of the books and some associated magazine articles, where links connected everything on the CD. In our work, we addressed some content issues and many presentation issues, and we produced enough innovations to merit an article for practitioners in Microsoft Internet Developer and a paper for academics in Proceedings of the 5th Conference on Human Factors & the Web.

I recently found myself in the directory with the CD's files, and I took the opportunity to review the notes I'd made regarding how we could improve the CD were we to undertake the project again (e.g., as a second edition). Most of the comments were specific either to the content of the CD or to the web-browser-as-book-viewer decisions we made (hence not germane to my work on Fastware!), but some remain relevant today. Here they are (in no particular order):

• Text in graphics should be visible to search engines. (This generalizes: text in figures, tables, diagrams, animations, etc., should be visible to search engines.)
  
  
• Electronic versions of books are essentially software and, like contemporary software, they should be updatable via the net. When bugs are fixed in an electronic version of a book, owners of that book have a right to expect to be able to incorporate those bug fixes into the book they've purchased.
  
  
• The books on my CD are organized into either 35 or 50 "Items," which are essentially technical essays. Each book has an extensive set of cross references among its Items, so Item 22 might refer to Item 21 and Item 8. Within a book, this was fine, but when I added links between the books' Items (a feature exclusive to the CD), I had to make clear which book had the Item I was referring to. That is "Item 22" was unambiguous within a print book, but it wasn't unambiguous on a CD with two books, each of which had such an Item. I addressed this by prepending a book-specific letter to the Item number for Items outside the current book, e.g., "Item 22" is in the current book, but "Item M22" or "Item E22" is in the other book.
  
  A fair number of people found this confusing. One way to address this problem would have been to always use the E or M prefix on all Item cross references, but this would have introduced syntactic noise and led to the electronic books not looking the same as their print versions.
  
  The real problem, I think, is trying to figure out how to write for something that might stand alone (as, e.g., a print book) but that might also be part of a collection of interlinked documents. Readers of the standalone version shouldn't be bothered with cross reference disambiguation overhead that's needed only in non-standalone environments, but books they know from their standalone versions should look essentially the same as the versions they encounter in linked environments. (For a related discussion, consult my vision for electronic books.)
  
  
• Because link text generally looks different from non-link text, it calls attention to itself. That's the point of it looking different: to communicate, "Hey, I'm clickable!" Unfortunately, when too much text tries to get your attention at the same time, it intrudes on the reading experience. For example, contrast this, where every reference to Amazon is linked,
  

  You can buy lots of stuff at Amazon. That's because Amazon sells lots of stuff. Amazon customers expect lots of stuff at Amazon, because that's what Amazon is know for. Yay, Amazon!
  

  with this, where only the first reference is linked:
  

  You can buy lots of stuff at Amazon. That's because Amazon sells lots of stuff. Amazon customers expect lots of stuff at Amazon, because that's what Amazon is know for. Yay, Amazon!
  

  Failing to make links out of text that's already been made a link recently is, to me, akin to using pronouns to refer to nouns that have been recently introduced. Pronouns make text more interesting and less repetitive, but harder to understand out of context. Non-link text is similar: it avoids visual repetition, but it makes the text harder to understand out of context.
  
  There are two additional issues relating to whether repeated text should be made active at each point of repetition. The first has to do with consistency. More than one reader of my CD complained that I was inconsistent about what text was linked and what was not. These readers seemed to expect all naturally linkable text to be linked, no matter how many times that text occurred, even within a short space.
  
  The other additional issue concerns search engines, which can plop you down in an arbitrary location in an arbitrary document. If you start reading and you encounter a pronoun, you naturally scan backwards looking for the antecedent. But if you encounter text that seems like it should be a link, my guess is that you don't scan backwards looking for the same text in link form. Rather, you get annoyed at the author for failing to make the text you're looking at a link. That leads to the challenge: how do you avoid the visual clutter that accompanies making every occurrence of naturally linkable text into a link while also meeting the link-related expectations of readers who use search engines to take them to the point in a document where they start reading?
  
  
• Clicking on naturally linkable text like "Item 5" or "Section 3.5.1" or "Chapter 4," where the target of the link generally has a title, leads to some readers wanting to see the title without having to traverse the link. Instead of
  

  As you'll see in Chapter 4, ...
  

  they'd prefer to see:
  

  As you'll see in Chapter 4 ("Giant Anteaters"), ...
  

  Some authors do this in print, but I find it distracting as a reader. As the author of an electronic book, I can offer the title as an option by, e.g., displaying it when the mouse hovers over the link text. But that means I have to make sure that capability is provided when my book is prepared for electronic publication. (A similar capability can be used to avoid making readers turn to a glossary to see a term's definition.)
  
  
• If I'm looking at an nth-level index entry, it would be nice to have an easy way to get to the n-1st level, i.e., essentially a way to move to the parent entry for a child index entry.
  
  
• One reader wrote:
  

  It would be great if you can have a table of content showing in the navigation area, and there is a toc synchronization function (much like Microsoft Workshops), so that the readers will have a better idea of where they are in the book.
  

  This is one way to address the "where am I?" problem that can arise as the result of a search or when following a link from one part of a document to another (or from one document to another).
  

An Introduction to Fastware!

All my blog entries to date have been about issues related to authoring: things that affect my choices among writing tools and my strategies for effectively conveying the information I want to get across to my readers. (As I've noted before, the term "reader" is misleading, because one of the forms in which I'd like Fastware! to be usable is audible. The proper term is probably "content consumer," but I'll stick with "reader," in part because it's a lot less ugly, in part because it better reminds me that I'm primarily writing for humans, not machines.) This blog entry is a bridge between authoring concerns and content issues, because it touches both.

Experienced authors and publishers will tell you that you usually write a book's introduction last, because you can't really know what needs to be introduced until you've written it. When working on my past books, I used the placeholder introductory chapter as a dumping ground for terms that needed to be defined, assumptions that needed to be explained, conventions that needed to be described, etc. When the book proper was done, I'd go back and sift through the debris that had made its way to what was to become the Introduction, take a deep breath, and do my best to make a coherent narrative out of the odds and ends I found there.

For Fastware!, I chose a different approach. My experience has been that the need for a book on how to write software that runs quickly is not self-evident to many people. That bothered me. I view the case as overwhelmingly strong, and I felt compelled to make that case right away. As a result, I wrote Fastware!'s Introduction first, and I've now made a draft available at the book's web site. In its current form, the chapter is more manifesto than Introduction, and I know I'll have to add more material once I've written the rest of the book, but it should give you a good idea of what I envision the book to ultimately be.

There are two parts to that vision, content and presentation, and the Introduction should give you a glimpse of both. (If you've been following this blog, you know that I believe that content and presentation are not really separable. If you haven't been following the blog and are interested in this view, check out this and this.) The content should be self-explanatory. If it's not, I've botched my job, and please let me know about it, either as comments on this blog or as email to smeyers@aristeia.com.

Regarding the draft presentation, here are a few things I think worth pointing out:

• The book is about speed, and visually, it should come across that way. One way I've tried to convey this is the use of italics in the chapter title, section and sidebar heads, and the footer. Like runners striving to move faster, italic letters lean forward. Another way is the fireball behind the chapter numbers. This is cheesy in its current form, but I have no illusions that I'm an artist; the fireball is a placeholder. My original idea was to have flames shooting out the back of the page numbers, and I'd ultimately like to do something more like that. Another problem with the fireball is that it's too prominent, but that can be toned down in various ways (e.g., increase the transparency of the image). The main thing is to come up with subtle ways to suggest movement -- fast movement -- through the book's layout and formatting.
• "Voice of Experience" sidebars reinforce material in the chapter they accompany. This is one of the ideas for Fastware! I'm particularly enthusiastic about, and it straddles the line between content and presentation. The book will contain lots of suggestions about how to write fast software, and after a while, I expect readers to roll their eyes and mutter, "Yeah, yeah, yeah..." Some of the suggestions may strike some readers as less important than I know them to be, and I worry that such readers will skip the muttering and simply roll their eyes.
  
  Some authors, to reinforce the points they make, offer fictional examples demonstrating how things could play out in practice. Other authors give real examples from their own experience. Few authors have the background to personally vouch for the full range of topics I'll cover in Fastware!, and, alas, I'm not one of them. The "Voice of Experience" sidebars are my way of bringing in guest speakers who, in their own words, can back up what Fastware! tells them. My plan is to have two sidebars per chapter, although I currently have only one in the draft Introduction.
  
  The sidebars are designed to have a different look to them, and not just to make it clear that they are sidebars. For readers reading straight through, I want them to pop up from time to time as visual and semantic treats. For readers flipping through the book, I want them to stand out as easy-to-find nuggets that stand on their own and provide useful "from the factory floor" information.
  
• Color output is the default. Especially as time goes on, I expect more and more readers to experience Fastware! on a color-capable device, so the primary presentation format should take advantage of color. In the draft Introduction, I sometimes use color to bring out semantics (e.g., for clickable URLs and email addresses, although they are not active in the PDF I posted, sorry). In other cases, I use color simply to make the work more visually engaging. Some will pooh-pooh this use of color, but it has as great an impact on a prospective reader's evaluation of a book as do things like font choices, interline leading, footnotes vs. endnotes, etc. Black electronic text on a white electronic page looks as anachronistic to contemporary readers as black and white TV shows do to contemporary TV viewers. In my draft introduction, I use color in a number of ways to enliven the visual effect: for section headers, for bold-faced text, for sidebar backgrounds, in the line above the footer, in the page number fireball, in "The Voice of Experience" photographs. My goal is to produce a book that looks somewhat less like a traditional book and somewhat more like magazines and web pages.

If you have any comments on my vision for Fastware! (content or presentation) or about the draft Introduction, please let me know, either as comments on this blog or via email to smeyers@aristeia.com.

XML, Structure, and DocBook

In my last post, I mentioned that all I really need to be able to produce is PDF and XML. PDF can be generated from suitable XML, and a colleague who works extensively with the publishing industry remarked that my leaning towards LaTeX was out of step with the industry's move towards XML-based content representation. In and of itself, that didn't strike me as terribly interesting. As I wrote to my colleague:

I don't doubt your observation that publishers are converging on XML as a representation format, but I don't think it's very meaningful. XML is just text in a particular syntactic format, and anything can be translated into XML: FrameMaker, Word, LaTeX, reST, HTML, you name it. Making sense of an XML document requires knowing the schema that assigns semantics to the document's elements, and my sense is that the publishing world is not converging on a common schema. O'Reilly uses DocBook. The Pragmatic Programmers use PML. Presumably Pearson uses something else. If I take my book in DocBook/XML format and give it to somebody whose tool chain expects XML using a different schema, that tool chain will be unable to do anything interesting with the document until it's been translated from DocBook XML to OtherSchema XML. Such a translation may be easy or difficult, depending on how well the semantic elements of the two schemas correspond.

Still, I started poking into information about generating XML from FrameMaker (what I've used for my previous books), and that led into a detour about the difference between Unstructured FrameMaker (the variant I've been using, where there is no document schema) and Structured FrameMaker (the variant that uses document schemas). Both can generate XML, but then I read an article at scriptorium.com that yielded an XML epiphany. The XML generated by Unstructured FrameMaker consists of a flat sequence of paragraphs identified by their styles, e.g.,

Book Title
Book Author
Book Chapter
Chapter Intro
Chapter Section
Section Para
Section Para
Chapter Section
Section para
Book Chapter
Chapter Intro
...

For purposes of generating PDF, this is fine, because all we need to know is how to format each paragraph style. But the flat sequence of paragraphs fails to reflect the underlying structure of the document. That looks more like this:

Book Title
Book Author
Book Chapter
  Chapter Intro
  Chapter Section
    Section Para
    Section Para
  Chapter Section
    Section para
Book Chapter
  Chapter Intro
...

The structural information isn't needed for typesetting, but it's present in my head as I write, and it's reflected in the eventual formatting (e.g., chapter titles are typeset bigger than section titles, which are typeset bigger than subsection titles, etc.), so having it present in the XML seems like a pretty reasonable notion. Furthermore, XML schemas used by the publishing industry for book representation are doubtless going to contain such information, so if I want to facilitate transformation of my book's XML into whatever XML a publisher might want, my XML needs to have the structural information the target XML will require.

In short, there XML and there's XML, and XML without structural information about the book content it represents almost certainly imposes serious restrictions on what can be done with it. Going down that road seems foolish.

My need, then, is to be able to generate XML that reflects the logical structure of my book. I thus need an XML schema that defines that structure. I could come up with one from scratch, but I'm not so näive as to believe that that's a simple task, or, more precisely, a simple task to do well. Call me a reuse buff, but I want to pick up a pre-fab book schema, assume that the people who developed it knew what they were doing, and get on to the real work of producing content. Which pretty much takes me back to DocBook and the search for a DocBook-aware XML editor.

Reining in Requirements

In an earlier post regarding support for custom color combinations, I wrote:

Being a software person, I'm going to give in to my inclination to generalize and assume that any given set of color choices is going to be problematic for some portion of my readership.

No problem, I still think that's reasonable. The problem is this part:

Being a software person, I'm going to give in to my inclination to generalize....

A friend who's been following this blog, who's an author who has prepared CRC (camera-ready copy) for several books, and who's currently working on a book where he'd like to satisfy many of the same requirements I would, suggested I consider -- I am not making this up -- Microsoft Word. Hope springing eternal, I posted a message to a couple of Word newsgroups asking whether Word was up to the task of producing multiple PDFs from a single document, where each PDF might have custom page dimensions and custom style definitions. To date I've seen no useful responses, but it occurred to me sometime after I'd posted my query that I'd made a classic software development mistake: I'd generalized my problem to the point where what I said I wanted to do was almost certainly beyond anything I'd ever need to do.

Sure, I want to produce content that can be viewed on devices of different physical sizes, and certainly that will result in different page sizes, but does that require different PDFs? I had the nagging feeling that it might not, and a little research into the formats employed by various electronic reading devices (e.g., Kindle, Sony Reader, iPhone, etc.) revealed that all break lines dynamically. Such "reflowable text" is a foundation of the epub standard. It's also contradictory to the idea behind PDF, which inherently assumes the existence of physical pages with a fixed size. Unsurprisingly electronic devices for reading hate PDF. The Mobipocket Developer Center, for example, lists six formats that can be used as the basis for importing content in order of desirability. PDF is number six.

Ebook devices tend to prefer some flavor of XML (often XHTML) as their content format, and that means that what I really need is a way for my authoring toolchain to produce two things: a single fixed-dimension PDF for print publication (which, with some minor processing, can perform double-duty as a directly-consumable eformat) and XML (or something directly convertible to XML). That combination of requirements is much less demanding than what I'd been thinking I needed.

In fact, now that I'm in a "what do I really need" mood, I can probably dump the per-order custom-color requirement, too. In a perfect world, yes, I'd offer each reader their choice of color combinations. In practice, I can probably make almost everybody happy by offering (1) a color document for color output devices and for people who don't suffer from any kind of color blindness and (2) a monochrome document for monochrome output devices and for people with any kind of color blindness. Where the color document uses color, the monochrome document could (for text) use underlining or changes in font face and (for diagrams) use different line thicknesses and fill styles. If Fastware! unexpectedly turns out to have nontrivial code examples where syntax coloring would be useful, I could offer variants using the most commonly employed color combinations, thus yielding e.g., (1a) color using Eclipse syntax highlighting, (1b) color using Visual Studio syntax highlighting, etc. As I said, I'd like to offer color customization on a per copy basis, but that's not a requirement, it's a desideratum. Those are different things. It's important that I not confuse them.

A Look at reStructuredText

Several comments on this blog referred me to reStructuredText (reST) as a markup alternative to LaTeX and DocBook. reST is part of the Docutils project, which, probably because I am not a Python programmer, I had not heard of.

I've now spent a little time reading about reST, examing some of its output, looking at some document source files, writing and processing some trivial examples, and posting questions to the Docutils mailing list. On a scale of knowledgability about reST that runs from 1 to 100, that puts me at about 1.1. Still, I've come to a few conclusions:

• For common things like numbered or bulleted lists, reST markup is less verbose (hence less intrusive) than LaTeX's.
  
• For inline style-based markup, they seem to be about the same. reST's :foo:`Text` is LaTeX's {\foo Text}.
• The LaTeX user community seems to be larger than reST's, and while there are several books on LaTeX, there don't seem to be any dedicated to reST or Docutils.
  
• reST documents are typically viewed as HTML, LaTeX documents as PDF. This is noteworthy, because I currently expect PDF generation to be more important for Fastware! than HTML generation.
  
• reST more rigorously separates content from presentation.

This last point may be the most interesting. As part of my kicking of reST's tires, I looked at some documents I'd written using LaTeX, trying to figure out how I'd be able to achieve the same effect in reST. I generally had little trouble, but then I noticed a table I'd included in an IEEE Software paper from long ago:

Each entry here is centered both horizontally and vertically, and it occurred to me that I'd never noticed such layout in tables generated from reST. I started googling around for centering support in reST, and, thanks to help from the Docutils mailing list, I eventually came to understand that there is no notion of "centering" in reST. Whether something is centered isn't content, it's presentation, and presentation decisions are made downstream from reST, e.g., by CSS style sheets for presentation via HTML.

Something else that became apparent is that while the above table could be produced from reST by slapping an appropriate "centering" attribute on the entire table, reST doesn't really have a way to express metadata (e.g., presentation information) on a cell-by-cell basis. So if I wanted some cells' content to be centered and others' to be, say, left-justified, reST isn't up to that. I can't think of a case where I'd want to do that, but I know of lots of cases where I create spreadsheets where some rows or columns use different justification settings. Here's part of the spreadsheet I've been using to compare link-related features of various electronic books:
Note that some columns are horizontally left-justified, while others are horizontally center-justified.

This takes us back to a topic I covered in one of my earliest posts: the lack of strict separation of content and presentation. The way information is placed in a table can help comprehension or it can hurt it, and as an author, I want to make sure that the presentation helps. Certainly the proper presentation of table information can vary from row to row and column to column within a table or between tables, and the fact that both Excel and LaTeX also offer per-cell formatting support strongly suggests that there are situations where content creators feel that such control is useful.

In response to one of my requests for information on the Docutils mailing list, David Goodger commented:

In terms of expressive power, LaTex > reST. In terms of readability and convenience, reST > LaTeX. Take your pick. If you're picky about the formatting details, reST may not be for you.

Alas, I am picky about formatting details, in part because I'm a control freak, but in part because I believe that formatting is related to comprehensibility, and, fundamentally, comprehensibility is pretty much the only thing that matters. (Okay, accuracy is kind of important, too.) An author's job is to convey his or her message as effectively as possible. That requires an expressive medium in which to represent that message. My concern is not so much that reST is less expressive than LaTeX, it's that it's less expressive than what I think I might reasonably want. I don't need the most expressive book-writing system available, I just need one that's adequately expressive. If reST doesn't offer a way for me to produce tables in a form I already know I employ, that's a problem.

reST looks to be a nice markup language, easy to learn and use for many purposes, especially the production of web pages. I was impressed with the low barrier to entry: I downloaded and installed Python and docutils and was producing HTML from reST in under an hour. It's not hard to find impressive-looking decidedly nontrivial web pages generated from reST (e..g, the Python multiprocessing documentation pointed out by David Niergarth or the pages at Saifoo). Still, I can't shake the doubt that if I go with reST, I'll eventually bump into something I want to be able to express, but can't. I'm therefore still leaning towards LaTeX.

Besides, I still have that friend who's offered to be my personal LaTeX consultant :-)